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Main conclusion: Rainwater most probably constitutes a relatively effective solvent for lichen substances in nature which have the potential to provide for human and environmental needs in the future. The aims were (i) to test the hypothesis on the potential solubility of lichen phenolic compounds using rainwater under conditions that partly reflect the natural environment and (ii) to propose new and effective methods for the water extraction of lichen substances. The results of spectrophotometric analyses of total phenolic metabolites in rainwater-based extracts from epigeic and epiphytic lichens, employing the Folin–Ciocalteu (F.–C.) method, are presented. The water solvent was tested at three pH levels: natural, 3, and 9. Extraction methods were undertaken from two perspectives: the partial imitation of natural environmental conditions and the potential use of extraction for economic purposes. From an ecological perspective, room-temperature water extraction (‘cold’ method) was used for 10-, 60-, and 120-min extraction periods. A variant of water extraction at analogous time intervals was an ‘insolation’ with a 100W light bulb to simulate the heat energy of the sun. For economic purposes, the water extraction method used the Soxhlet apparatus and its modified version, the ‘tea-extraction’ method (‘hot’ ones). The results showed that those extractions without an external heat source were almost ineffective, but insolation over 60- and 120-min periods proved to be more effective. Both tested ‘hot’ methods also proved to be effective, especially the ‘tea-extraction’ one. Generally, an increase in the concentration of phenolic compounds in water extracts resulted from an increasing solvent pH. The results show the probable involvement of lichen substances in biogeochemical processes in nature and their promising use for a variety of human necessities. [ABSTRACT FROM AUTHOR]

The present meta-analysis provides literature data on the effect of lichen extracts and single secondary metabolites used against Fusarium spp. moulds. Lichen extracts were obtained from 51 corticolous, 17 terricolous and 18 saxicolous lichen species and 37 secondary compounds were tested against eight fungal species, i.e., Fusarium acuminatum, F. avenaceum, F. culmorum, F. fujikuroi, F. oxysporum, F. roseum, F. solani and F. udum. The researchers used several test methods, mostly to determine MIC and IZ. Extracts were obtained using several solvents, mainly organic ones with use of the Soxhlet apparatus. The most frequently tested species was F. oxysporum, against which lichen substances from Alectoria sarmentosa, Cladonia mitis, C. rangiferina, Flavoparmelia caperata, Hypotrachyna cirrhata, Leucodermia leucomelos, Parmotrema austrosinense, P. reticulatum, Physcia aipolia, Pseudevernia furfuracea, Roccella montagnei and Umbilicaria nylanderiana and secondary metabolites such as 2-hydroxy-4-methoxy-3,6-dimethylbenzoic acid, atranorin, lecanoric and (+)-usnic acids showed the highest antifungal potential. These agencies could compete with the potential of fungicides, such as flucytosine and fluconazole. Other species have been poorly investigated. Statistical analysis of literature data showed that the fungistatic potential of lichen extracts is significantly different from individual secondary metabolites. Similarly, the potential of secondary metabolites often differs significantly from that of non-lichen substances. This meta-analysis indicates the potential of lichen substances as future anti-fusarial agents. [ABSTRACT FROM AUTHOR]

A systematic review of literature data on the antifungal potential of extracted lichen compounds and individual secondary metabolites against mold species of the genus Aspergillus is provided. Crude extracts from 49 epiphytic, 16 epigeic and 22 epilithic species of lichens and 44 secondary metabolites against 10 species, Aspergillus candidus, A. flavus, A. fumigatus, A. nidulans, A. niger, A. ochraceus, A. parasiticus, A. restrictus, A. stellatus and A. ustus, were analysed. Several measuring techniques were employed for such analyses. Lichen substances were extracted with alcoholic and other organic solvents mainly using the Soxhlet apparatus. Among the three most-studied mold species, the results showed that the crude extracts from the thalli of the lichens Cladonia foliacea, Hypotrachyna cirrhata, Leucodermia leucomelos, Platismatia glauca and Pseudevernia furfuracea against Aspergillus flavus, from C. foliacea, Nephroma arcticum and Parmelia sulcata against A. fumigatus and from Evernia prunastri, Hypogymnia physodes, Umbilicaria cylindrica and Variospora dolomiticola against A. niger have the greatest antifungal potential. The lichen secondary metabolites showed a higher inhibitory potential, e.g. protolichesterinic acid against A. flavus, lecanoric acid against A. fumigatus and orsellinic acid against A. niger; the other seven species of Aspergillus have been poorly studied and require further investigation. A comparison of the inhibitory potential of the tested mixtures of lichen substances and their secondary metabolites shows that they can compete with commonly used antifungal substances, such as ketoconazole and clotrimazole against A. flavus, A. nidulans, A. niger and A. parasiticus and fluconazole in the case of A. fumigatus. [ABSTRACT FROM AUTHOR]

The antifungal activity of secondary lichen metabolites extracted by means of acetone and ethanol from Cetraria islandica, Cladonia mitis, C. rangiferina, Pseudevernia furfuracea and Usnea dasopoga on the pathogenic fungi Fusarium oxysporum and F. avenacuem was examined. The activity of extracted compounds was tested after their mixture with PDA medium before solidification. The most active extracts inhibiting the growth of fungal mycelia contained fumarprotocetraric, salazinic and usnic acids, and atranorin. Unparalleled activity was demonstrated by an ethanol extract from mixed C. islandica and P. furfuracea thalli, which accelerated the growth of F. avenaceum compared with the control test with ethanol. The growth rate of the two Fusarium representatives was strongly inhibited by both alcoholic extracts from C. mitis and from C. rangiferina, more strongly than by the extracts from the mixed thalli of the two terricolous taxa. A dose of 1 ml of acetone added to the medium had no significant effect on the growth of the tested fungi; it indicates usefulness of acetone as a solvent for some lichen compounds in this type of experiment. [ABSTRACT FROM AUTHOR]

The phenolic, flavonoid, tannin and proanthocyanidin content of the lichen Cladonia foliacea with and without its lichenicolous fungus Heterocephalacria (Syzygospora) bachmannii was investigated. The phenolic compounds were quantified in organic extracts using ultrasonic extraction (acetone and methanol) and in milled material (the ground material diluted with microcrystalline cellulose). The total phenolic content depended on the solvent polarity, the extraction technique and the species. The results demonstrated that the highest total phenolic content was recorded in untreated milled material (935.75 μg GAE/g DW) of H. bachmannii plus C. foliacea, followed by C. foliacea (668.29 μg GAE/g DW). The antioxidant activities were evaluated by the in vitro scavenging capacity, iron reducing power, and iron chelating power. The results showed that the highest scavenging capacity were obtained in methanol extracts of C. foliacea with IC50 = 0.015 mg/mL, followed by methanolic extract of H. bachmannii plus C. foliacea that had a scavenging capacity and iron reducing power of (IC50 = 0.030 mg/mL and IC50 = 0.054 mg/mL, respectively). The milled material showed the highest iron chelating power (IC50 = 0.279 mg/mL). We conclude that Cladonia foliacea when parasitized by H. bachmannii possesses a high antioxidant potential in the methanolic extract. Acetone and methanol extracts, showed that extracts from lichen plus lichenicolous fungus contained different and possibly more effective bioactive molecules than the lichen alone. These included phenolic acids, alkanes and aromatic compounds. This is the first study to investigate the phenolic content and antioxidant capacity of a lichenicolous fungus, albeit based on differences between the lichen with and without the mycoparasite H. bachmannii. [ABSTRACT FROM AUTHOR]

The article presents an obituary for lichenologist Vernon Ahmadjian.

The largest family of lichen-forming fungi, the Parmeliaceae, is reviewed. It includes 79 genera in current use and ca 2726 species, a large majority of which belong to one of five main clades: the parmelioid, cetrarioid, usneoid, alectorioid and hypogymnioid. However, 21 genera are positioned outside these clades, and four genera in current use still lack DNA- data. The family has been shown to be monophyletic and the generic classification is relatively well-settled compared with other lecanoralean families. Each clade and its genera are presented here with the latest results from phylogenetic analyses and current taxonomy. In addition, a historical outline of the family and its most prominent researchers is provided. [ABSTRACT FROM AUTHOR]

Fourteen genera belong to a monophyletic core of cetrarioid lichens, Ahtiana, Allocetraria, Arctocetraria, Cetraria, Cetrariella, Cetreliopsis, Flavocetraria, Kaernefeltia, Masonhalea, Nephromopsis, Tuckermanella, Tuckermannopsis, Usnocetraria and Vulpicida. A total of 71 samples representing 65 species (of 90 worldwide) and all type species of the genera are included in phylogentic analyses based on a complete ITS matrix and incomplete sets of group I intron, β-tubulin, GAPDH and mtSSU sequences. Eleven of the species included in the study are analysed phylogenetically for the first time, and of the 178 sequences, 67 are newly constructed. Two phylogenetic trees, one based solely on the complete ITS-matrix and a second based on total information, are similar, but not entirely identical. About half of the species are gathered in a strongly supported clade composed of the genera Allocetraria, Cetraria s. str., Cetrariella and Vulpicida. Arctocetraria, Cetreliopsis, Kaernefeltia and Tuckermanella are monophyletic genera, whereas Cetraria, Flavocetraria and Tuckermannopsis are polyphyletic. The taxonomy in current use is compared with the phylogenetic results, and future, probable or potential adjustments to the phylogeny are discussed. The single non-DNA character with a strong correlation to phylogeny based on DNA-sequences is conidial shape. The secondary chemistry of the poorly known species Cetraria annae is analyzed for the first time; the cortex contains usnic acid and atranorin, whereas isonephrosterinic, nephrosterinic, lichesterinic, protolichesterinic and squamatic acids occur in the medulla. Notes on the anatomy of Cetraria annae and Flavocetraria minuscula are also provided. [ABSTRACT FROM AUTHOR]

FT-Raman spectra have been obtained from the highly pigmented lichen Cryptothecia Rubrocincta from a Brazilian vestigial rainforest habitat. Spectral signatures of the two mare lichen substances, chiodectonic acid and confluentic acid, were identified in adjacent zones of the thallus Of the characteristic zonal colours displayed by the thallus, the outer red zone contained chiodectonic acid arid no calcium oxalate, and graded into by a pink zone with calcium oxalate monohydrate (whewellite) in association with chiodectonic acid, to the inside of which is a concentric white zone containing calcium oxalate dihydrate (weddellite); however, chemically differentiated sites (elliptical brown flecks with a major axis of c, 15 mu;m) in both the pink and red zones contained chiodectonic acid and calcium oxalate monohydrate. The role of Raman spectroscopy in the spatial identification of lichen substances in the thallial structures is demonstrated. [ABSTRACT FROM AUTHOR]

Illustrated descriptions are provided for four new lichen species found in The Seychelles: Arthothelium feuereri Aptroot & Seaward, Dimerella straminea Aptroot & Seaward, D. subs quamosa Aptroot & Seaward and Fellhanera silhouettae Aptroot & Seaward. [ABSTRACT FROM AUTHOR]

The article discusses the historical records and contributions of the lichens at the Lawnswood Cemetery in Leeds, England. It examines the increase population of lichens in urban churchyards which could lead to health hazards in the public. It presents a lists of lichen species found in memorials, walls and buildings including Acarospora fuscata, Lecidella carpathica and Rhizocarpon distinctum.

An obituary for Margalith Galun, former editor and founder of the international journal "Symbiosis," is presented.

The article focuses on the proposal to conserve the name Lichen muralis (Lecanora muralis, Protoparmeliopsis muralis) with a conserved type (Ascomycota: Lecanorales: Lecanoraceae). Topics discussed include Schreber's name for the fungi being illegitimate as he cited Lichen pallescens L. as a synonym, and the corticolous species is now being called Ochrolechia pallescens and is protected with a conserved type.

The article reviews the publication "Lichen Distribution Maps- A World Index and Bibliography," by Peter Scholz.